Railway vehicles traditionally include a car body that rides on top of a chassis or framework referred to as a truck, which serve as a modular subassembly of wheels and axles. A traditional rail truck includes two side frames that run parallel to the direction of travel of the truck. A pair of wheel sets span between and support each side frame at respective end locations. Each wheel set includes an axle that runs generally perpendicular to the side frames, and a pair of wheels at each end of the axle. A bolster also spans across the side frames, typically in a central location of the truck, linking the side frames together. The bolster is also used to support or carry the car body, often via a bowl assembly (called a center bowl), positioned on an upper surface at the center of the bolster.
The center bowl serves as a mating structure that interacts with a corresponding connector or draft sill structure on the bottom of the car body. For example, the bolster center bowl may receive and support a protruding circular center plate of a draft sill that is associated with the car body, thereby providing a bearing surface that supports the car body on the truck bolster. Bolsters may utilize wear liners to improve the wear characteristics and extend the service life of the bolster. For instance, the bolster may utilize a horizontal wear plate that spans a bottom surface of the center bowl and a vertical wear ring that circumscribes an interior circumference of the bowl to absorb wear and tear that results at the interface with the rail car connector. In this way, the wear liners can be replaced piecemeal when wear becomes significant, as opposed to changing out the entire bolster. Often times, these wear liners are welded to the center bowl, which makes the replacement process difficult and time consuming.